Fig. 10. The rates of Ca²⁺ removal following depolarization- and InsP₃-induced increases in [Ca²⁺]_c were reduced by 8-bromo cADPR. (A) The membrane permeable cADPR antagonist, 8-bromo cADPR (20 µM, added to the bath), significantly slowed the rate of Ca²⁺ removal following the increases in [Ca²⁺]_c (ai and bi) produced either by InsP₃ (, ai,iii; n=6) or depolarization (–70 mV to +10 mV, bi,iii; n=6). (B) Inhibition of Ca²⁺ removal mechanisms [ii; mitochondria, SR Ca²⁺ pump and Na⁺-Ca²⁺ exchange using CCCP and oligomycin (OL) Na⁺-free bathing solution (NaF) and thapsigargin (TG) together] significantly slowed the rate of decline following depolarization-evoked (–60 mV to +10 mV) [Ca²⁺]_c increases. Thereafter, 8-bromo-cADPR was added (iii) in the continued presence of the removal inhibitors; this increased the baseline [Ca²⁺]_c and slowed further the rate of [Ca²⁺]_c decline (notice the increased time base on iii) (summarised in Bb) (*P<0.05; n=5-7 for each data point).

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